TUESDAY, May 13 (HealthDay News) -- The quality of care at hospitals that treat poor and underserved patients, often called safety-net hospitals, is lagging well behind hospitals that do not serve these patients, a new study finds.

These hospitals, which rely on state and federal funding from Medicaid and other sources, do not have the money to improve the quality of care at the same rate that better-funded hospitals do.

"Safety-net hospitals provide a lower quality of care than non-safety-net hospitals," said lead researcher Dr. Rachel M. Werner, from the Philadelphia VA Medical Center. "Over time, the quality was lower than non-safety-net hospitals."

This is important, because hospital performance determines the funding that many hospitals get under pay-for-performance policies, Werner said. "Hospitals that are doing worse are going to get penalized," she said.

"Finances at safety-net hospitals are often worse than at non-safety-net hospitals," Werner said. "This is because they provide more care to uninsured patients and more care for Medicaid patients. With less money, they have less to put into quality improvement."

Under pay-for-performance, a system that rewards quality care, safety-net hospitals fare worse, Werner added. "You get into a situation where rich hospitals get richer, but the poor hospitals become poorer," she said.

Her report is published in the May 14 issue of theJournal of the American Medical Association.

In the study, Werner's team used data collected between 2004 and 2006 from 3,665 safety-net and non-safety-net hospitals.

The researchers found that hospitals that cater to a low percentage of Medicaid patients had significantly more improvement in quality compared with safety-net hospitals.

For example, hospitals that have a low number of Medicaid patients improved the care of heart attack patients by 3.8 percentage points compared with safety-net hospitals, whose performance improved 2.3 percentage points.

This means that there was a 39 percent difference between safety-net and non-safety-net hospitals in caring for heart attack patients. The same pattern was repeated in the other conditions looked at, which included heart failure and pneumonia.

Moreover, hospitals, with a high percentage of Medicaid patients were less likely to be ranked by the U.S. Centers for Medicare and Medicaid Services as top performers. In fact, hospitals with a high percentage of Medicaid patients saw their quality ratings drop from 10.1 percent in 2004 to 2.8 percent in 2006, the researchers found.

At the same time, hospitals that treat a low percentage of Medicaid patients saw their quality ratings increase from 13.6 percent to 19.7 percent across all three medical conditions measured.

Werner thinks the solution to these problems is to provide safety-net hospitals with government funding specifically targeted to improving the quality of care. "The financial incentives should be restructured to reward improvement efforts, rather than achievement, safety-net hospitals could benefit," she said.

If the situation doesn't improve, the disparity between hospitals will only worsen, Werner said.

"This is concerning, because there are people who rely on these hospitals for their care, and ultimately you end up penalizing those patients by allowing this disparity to widen," Werner said. "It's possible that some of these hospitals will be forced to close. And this is a concern, because they provide an avenue of health care for many people who can't go elsewhere."

One expert also thinks the government needs to take the lead in improving the quality of care in safety-net hospitals.

"To improve care, you have to have resources," said Dr. Donald M. Berwick, a professor of pediatrics and health policy and management at Harvard Medical School, and president and CEO of the Institute for HealthCare Improvement. "This study confirms that very stressed organizations, that are living hand-to-mouth, are going to have trouble making improvements."

Berwick thinks it's going to take a large investment of government monies to improve quality at these hospitals.

"We ought to, as a nation, regard improvement of health care as a public good," Berwick said. "It's not just a matter of market pressures, but it's something we invest in as a society. We are a nation that needs public sector health care. We need health care to be just, and that means we need safety-net systems, and that means we need to help them."